Geology, features of modern evaporate sedimentation and salt accumulation are considered, and science-methodical grounds of ecogeological principles of Baskunchak Lake salt deposit rational use are given. Structure and the main laws of this natural system functioning are considered. A special attention is paid to the unique characteristic of the deposit, namely capacity to restore the resources after some time. This phenomenon is called "natural resources of salt accumulation". According to our field data, estimation of the "natural resources of salt accumulation" value is given. It allows assuming that annual salt output should be limited with the value of exploitation stocks, i.e. with such quantity of salt which can be restored by salt accumulation natural resources of the given deposit. The causes which create obstacles to rational use of Baskunchak today are shown, the ways of these problems solving are determined, and necessary conditions for going over to such type of exploitation are offered.